There are various roller clamp-type and other flow control devices which regulate fluid flow in flexible tubing. At present, these existing devices are used extensively in the pharmaceutical industry, principally to control the flow of intravenous solution into a patient's body. Although designed principally for pharmaceutical uses, these flow control devices also find application in other areas, for example, in laboratory experimentation, the photographic industry, and chemical processing.
In the assembly of existing devices, the manufacturer has often struggled with the problem of threading the flexible tubing through the device. This problem has been so severe that automated assembly of such devices in conjunction with flexible tubing is generally not possible. Thus, the production of existing devices has required human piecework assembly as a result of manually inserting the flexible tubing through the devices, a labor intensive task, which increases the cost of the valve. Moreover, the devices of the prior art do not provide for a positive means of regulating the flow of fluid through the flexible tubing. The devices of the prior art allow the flow setting to change if the device is touched or the flexible tubing is inadvertently jarred or tugged.